Well I'm sort of new to the car audio thing, so I'm not sure if overpowering my subs that much will be good for them? The two of them are rated at 350wmrs each.
That's not a problem at all. Say the amplifier is rated for over 1000watts RMS at 1% THD. This rating is usually based on 14.4 volt battery (which you car does not provide) and using some kind of synthetic test tones. Do you play a sine waves and turn up the volume until the amp puts out 1000watts? No. You probably listen music. Simply adjust your subwoofer amplifier gains to blend with the front speakers and don't worry about it.
